<?php
/******************
 * PageRankXor32 class created by MagicBeanDip
 * PageRank class was created by others
 * Look for updates at http://v1.magicbeandip.com/mbd-file/PageRankReport.php
 * This code is released into the Public Domain
 *
 * Sample use:
 * include('PageRankXor32.php');
 * $oPR=new PageRankXor32();
 * echo $oPR->getRank('http://www.amazon.com');
 *
 ******************/
 
//print("<br><br>\n\nPageRank32_script.php is loaded !!!<br><br>\n\n");

define('GOOGLE_MAGIC', 0xE6359A60);

// Use this class if your server is having problems with bitwise operations
class PageRankXor32 extends PageRank {
	function xor32($a, $b) {
		return $this->int32($a) ^ $this->int32($b);
	}
	//return least significant 32 bits
	//works by telling unserialize to create an integer even though we provide a double value
	function int32($x) {
		return unserialize("i:$x;");
		//return intval($x); // This line doesn't work on all servers.
	}
	
	function mix($a,$b,$c) {
		$a -= $b; $a -= $c; $a = $this->xor32($a,$this->zeroFill($c,13));
		$b -= $c; $b -= $a; $b = $this->xor32($b,$a<<8);
		$c -= $a; $c -= $b; $c = $this->xor32($c,$this->zeroFill($b,13));
		$a -= $b; $a -= $c; $a = $this->xor32($a,$this->zeroFill($c,12));
		$b -= $c; $b -= $a; $b = $this->xor32($b,$a<<16);
		$c -= $a; $c -= $b; $c = $this->xor32($c,$this->zeroFill($b,5));
		$a -= $b; $a -= $c; $a = $this->xor32($a,$this->zeroFill($c,3));
		$b -= $c; $b -= $a; $b = $this->xor32($b,$a<<10);
		$c -= $a; $c -= $b; $c = $this->xor32($c,$this->zeroFill($b,15));
		return array($a,$b,$c);
	}
}	

//This class should work on most servers
class PageRank {
	function zeroFill($a, $b){
		$z = hexdec(80000000);
		if ($z & $a){
			$a = ($a>>1);
			$a &= (~$z);
			$a |= 0x40000000;
			$a = ($a>>($b-1));
		}else{
			$a = ($a>>$b);
		}
		return $a;
	}
	
	function mix($a,$b,$c) {
		$a -= $b; $a -= $c; $a ^= ($this->zeroFill($c,13));
		$b -= $c; $b -= $a; $b ^= ($a<<8);
		$c -= $a; $c -= $b; $c ^= ($this->zeroFill($b,13));
		$a -= $b; $a -= $c; $a ^= ($this->zeroFill($c,12));
		$b -= $c; $b -= $a; $b ^= ($a<<16);
		$c -= $a; $c -= $b; $c ^= ($this->zeroFill($b,5));
		$a -= $b; $a -= $c; $a ^= ($this->zeroFill($c,3));
		$b -= $c; $b -= $a; $b ^= ($a<<10);
		$c -= $a; $c -= $b; $c ^= ($this->zeroFill($b,15));
		return array($a,$b,$c);
	}
	
	function GoogleCH($url, $length=null, $init=GOOGLE_MAGIC) {
		if(is_null($length)) {
			$length = sizeof($url);
		}
		$a = $b = 0x9E3779B9;
		$c = $init;
		$k = 0;
		$len = $length;
		while($len >= 12) {
			$a += ($url[$k+0] +($url[$k+1]<<8) +($url[$k+2]<<16) +($url[$k+3]<<24));
			$b += ($url[$k+4] +($url[$k+5]<<8) +($url[$k+6]<<16) +($url[$k+7]<<24));
			$c += ($url[$k+8] +($url[$k+9]<<8) +($url[$k+10]<<16)+($url[$k+11]<<24));
			$mix = $this->mix($a,$b,$c);
			$a = $mix[0]; $b = $mix[1]; $c = $mix[2];
			$k += 12;
			$len -= 12;
		}
		$c += $length;
		switch($len){
			case 11: $c+=($url[$k+10]<<24);
			case 10: $c+=($url[$k+9]<<16);
			case 9 : $c+=($url[$k+8]<<8);
			/* the first byte of c is reserved for the length */
			case 8 : $b+=($url[$k+7]<<24);
			case 7 : $b+=($url[$k+6]<<16);
			case 6 : $b+=($url[$k+5]<<8);
			case 5 : $b+=($url[$k+4]);
			case 4 : $a+=($url[$k+3]<<24);
			case 3 : $a+=($url[$k+2]<<16);
			case 2 : $a+=($url[$k+1]<<8);
			case 1 : $a+=($url[$k+0]);
		}
		$mix = $this->mix($a,$b,$c);
		/* report the result */
		return $mix[2];
	}
	
	//converts a string into an array of integers containing the numeric value of the char
	function strord($string) {
		for($i=0;$i<strlen($string);$i++) {
			$result[$i] = ord($string{$i});
		}
		return $result;
		}

	//returns -1 if no page rank was found
	function getRank($url){
		$ch = "6".$this->GoogleCH($this->strord("info:" . $url));
		
		$pagerank=-1;
		$fp = fsockopen("www.google.com", 80, $errno, $errstr, 30);
		if (!$fp) {
//			echo "$errstr ($errno)<br />\n";
			$pagerank = -1;
		} else {
			$out = "GET /search?client=navclient-auto&ch=" . $ch .  "&features=Rank&q=info:" . $url . " HTTP/1.1\r\n" ;
			$out .= "Host: www.google.com\r\n" ;
			$out .= "Connection: Close\r\n\r\n" ;
			fwrite($fp, $out);
			while (!feof($fp)) {
				$data = fgets($fp, 128);
				$pos = strpos($data, "Rank_");
				if($pos === false){
				}else{
				$pagerank = trim(substr($data, $pos + 9));
				}
			}
			fclose($fp);
		}
		return $pagerank;
	}
} 